Facilities at home and Gibraltar constrained the carrier before detailed design matured because a larger ship would fit fewer existing docks. Political comparison with Eagle and Ark Royal also made a conspicuously larger replacement difficult to defend. Costs were expected to rise rapidly above 45,000 tons, while the choice between 28 and 30 knots changed the required shaft layout and expense. Director-General of Ships A. J. Sims warned that some staff requirements could not fit below 45,000 tons and wanted to avoid imposing American-carrier demands on a modest British hull. The naval staff had asked designers to maximize aircraft capacity inside a limited displacement, so the requirements were already pulling against the design constraints.
Notable Point · 15:49-17:12
Dockyards, displacement, and CVA-01's size ceiling
CVA-01 had to be large enough for a credible air group yet small enough for British dockyards, political acceptance, and a cost curve that rose sharply above 45,000 tons.